Cutting bits are used in the heavy construction industry to cut and bore through rock and earth in the construction of highways, bridges, tunnels, dams and buildings of all types. Typical roadway surface reclaiming machines disclosed in the prior art include rotary driven cylindrical drums with holders holding fixed one of more cutting bits which scarify and mine the top portion of an asphaltic read surface. While several styles of drums have been employed, at least some styles have included an array of cutting bit holders fixed usually by a peripheral weld to the drum surface. Replaceable cutting bits are received within the cutting bit holders which can be periodically replaced as needed. Examples of prior art cutting bit holders are to be found, as non-limiting examples, in U.S. Pat. Nos. 3,865,437, 5,884,979, 5,582,468 and 5,098,167, the disclosures of which are incorporated by reference in their entireties. Other examples appear as the prior art cited in these patents.
During the operation of such roadway surface reclaiming machines, the cutting bits are exposed to extreme frictional and impact forces. Although these bits are typically manufactured from hardened materials, wear and damage to the cutting bits is inevitable. As the cutting bits wear, the efficiency of the equipment that relies upon them is reduced, slowing the reclamation process and increasing the burdens imposed upon the rutting hit holders, the cutting drums and the equipment that drives these devices. This leads to delay and increased costs for additional maintenance and labor.
However, typical road surface reclamation devices use a large number of cutting bits, thus, the replacement of the cutting bits is a time consuming process, largely because the manual removal and reinstallation cutting bits is often tedious and slow. Thus, replacement of the bits is expensive, both requiring the extended attention of one or more trained mechanics, and because all road reclamation operations must cease during replacement of the cutting bits. When circumstances dictate that cutting bits must be replaced during regularly scheduled reclamation activities, hundreds of labor hours can be lost.
Accordingly, what has been sought has been a tool for removing the cutting bits from their holders or directly from the cutting equipment in a tune effective manner.
However it is often very difficult to remove cutting bits from cutting bit holders. Cutting bits are firmly affixed when they are installed. In operation, the extreme stress, thermal conditions, and environmental contamination to which these products can be exposed can tightly bind these devices.
Thus, what is needed is an effective tool for separating even tightly bound cutting bits from their holders or from the cutting equipment in a time effective manner.
It might appear that a simple solution to this problem lies in providing, a powerful device that can exert exceptional amounts of force upon the cutting bit and bit holder in order to separate these components. However, great care must be exercised in the application of large amounts of force to this equipment because the individual cutting bit holding elements in rotary driven cylindrical cutters are often aligned in a known manner to maximize the mining activity and facilitate removal of mine material from the kerf created by the cutting operation. In certain alignment regimens, cutting bit holding elements on one side of the drum are aligned differently than cutting bit holding elements on the opposite side of the drum. Adherence to these alignment regimens is critical to the overall efficiency of the road reclamation process. Because of this, simply providing a tool that uses substantial amounts of force to separate these components will not meet the design objectives unless this force is properly directed and channeled to prevent damage to the cutting bit holders and the drum.
Accordingly, what is needed is an effective tool for separating even tightly bound cutting bits from their bit holders or the cutting equipment in a time effective manner while limiting the risk of damage to the cutting bit holder and the cutting equipment.
In situations where substantial amounts of force are required to separate the cutting bit from the cutting bit holder or the cutting equipment, it is occasionally the case that the cutting bit and cutting bit holder separate rapidly. When this occurs it is possible that the cutting bit will he accelerated and will gain some freedom of motion during the removal process. It is, therefore, necessary that the freedom of motion available to the cutting bit is restricted in order to limit the possibility that the cutting bit will unexpectedly contact the user of the tool, the cutting bit holder or the drum.
U.S. Pat. No. 6,526,641, the disclosure of which is incorporated by reference in its entirety, describes a tool for extracting cutting bits that employs a retractor device using a fluid-powered cylinder, where the can be a pneumatic or hydraulic fluid.
Notwithstanding, what is needed is an effective hand-operated tool for separating tightly bound cutting bits from their holders in a time effective manner while limiting the risk of damage to the cutting bit holder and the cutting equipment during the separation process.